Marine propulsion steering stabilizing structure



E. LEIPERT Jan. 12, 1960 MARINE PROPULSION STEERING STABILIZING STRUCTURE Filed Aug. 29, 1958 l-EIIEI INVENTOR. [aw/v60 ZV/ EEf A fra /vex United States Patent Ofiice 2,920,599 Patented Jan. 12, 196

MARINE PROPULSION STEERING STABILIZING STRUCTURE Edward Leipert, New York, N.Y.

Application August 29, 1958, Serial No. 758,149

4 Claims. (Cl. 115-35) This invention relates to devices for counteracting torque reaction in marine propulsion devices having steerable propellers and fixed engines.

In presently known outboard marine propulsion devices hereinafter referred to as outboard motors, it is the custom to either steer the vessel by rotating both the engine and the propeller section of the drive or to mount the engine in a fixed position upon the vessel and steer by means of rotating only the propeller section. Where both the propeller section and the engine are free to rotate for steering purposes, the reaction to the torque produced by the engine is absorbed by the same structure which resists the torque reaction of the bevel driving gear turning the propeller. Since these two reactions are opposed to each other, they cancel out and therefore substantially no steering problem is encountered with this type of construction.

However, in the outboard motor employing a structure which steers by rotating only the propeller section, there is a tendency for the steerable lower portion of the device to revolve because of torque reaction. This rotary force is created principally by the reaction to the torque being transmitted to the propeller through the bevel driving gears which carry the power of the engine to the propeller. The reaction or rotary force in the stationary or fixed engine type of drive therefore creates a constant pressure against the vessels steering mechanism when the propulsion device is in operation. This is, of course, tiring for the operator and requires constant attention.

Accordingly, it is an object of the present invention to overcome the reaction or rotary force in the steerable propeller type of outboard drive where the motor remains in a fixed position.

Another object of the present invention is to improve the steering properties of outboard motors of the steerable propeller type.

A further object of the present invention is to overcome the torque set up by the propeller in a steerable propeller type outboard motor without interposing frictional means or drag which would increase the force necessary for normal steering.

An object of the present invention is to provide a stabilizing element in an outboard motor to overcome the forces set up by rotary power sources.

A further object of the present invention is to use the principles of the gyroscope incorporated within the propeller drive housing of the outboard drive mechanism to resist undesired forces.

A feature of the present invention is its use of a gyroscope driven by the engine which drives the propeller.

Another feature of the present invention is the incorporation of a gyroscope within the propeller drive housing of an outboard motor.

Still another feature of the present invention is the incorporation of a gyroscope within the steering section of. an outboard motor.

The invention consists of the construction, combination and arrangement of parts as herein illustrated, described and claimed.

In the accompanying drawings, forming a part hereof, are illustrated two forms of embodiment of the invention, in which drawings similar reference characters designate corresponding parts, and in which:

Figure 1 is a view in side elevation partly cut away of the propeller drive housing and propeller of an outboard propulsion device showing one complete embodiment of the present invention.

Figure 2 is a view in side elevation partly broken away of a second embodiment of the present invention showing the incorporation of a gyroscope within the rudder or skag of an outboard drive unit.

Referring to the drawing and particularly to Figure l, 10 indicates the submerged steerable portion of the propeller drive mechanism of an outboard motor, having a supporting member 11 through which runs the vertical propeller drive shaft 23 from the engine (not shown) to the housing 10; A bevel gear 12 is secured to the end of the shaft 23 and is in mesh with a driven bevel gear 13. The bevel gear 13 is securely attached to the horizontal propeller shaft 24. A propeller 14 is secured to the shaft 24 in the well known manner.

The power required to turn the propeller 14 is transmitted from the power source (not shown) by the vertical propeller shaft 23 through the bevel gears 12 and 13. Since there is a torque action involved in the transmission of this power through the gears 12, 13, there is a substantially equal torque reaction transmitted to the freely secured steerable portion of the propeller drive mechanism housing 10 by virtue of the fact that it supports and contains the gears 12, 13.

The horizontal propeller shaft 24 extends into the housing 10 and is connected through an oil pump 32 to a step-up train of gears hereinafter referred to as the step-up gear cluster 15. The step-up gear cluster 15 terminates in a high speed shaft 16 which is supported at each end by ball bearings 22 and 22A. The oil pump 32 is located in the housing 10 for the purpose of circulating oil through the outboard motor gear drive.

A gyroscope disc or flywheel 17 is freely mounted on the shaft 16. Power is applied to the flywheel 17 from the shaft 16 through friction plates 18 which are splined to the shaft 16. Pressure to the friction plates 18 is obtained by means of a shaped flat spring 20 which compresses the plates 18 against the flat side surfaces 19 of the flywheel 17. An adjusting nut 21 which is screwed upon the end of the high speed shaft 16 is employed for the purpose of regulating the amount of spring pressure applied by the fiat spring 20. The purpose of the friction type of drive for turning the flywheel is to relieve some of the stress on the driving mechanism which may be quite severe during acceleration and deceleration, due to the high rotative speed of the flywheel. At these periods of high inertia, some slippage will occur and absorb a portion of the stress.

Referring to Figure 2 it will be seen that the flywheel 17 is driven from a train of bevel gears in mesh with gear 13 on the propeller shaft 24. The flywheel 17 rotates in a plane at right angles to that of the propeller in the second embodiment of the invention, whereas the flywheel 17 rotates in a plane parallel with the propeller in the first embodiment of the invention. In the embodiment shown in Figure 2 the flywheel 17 is located within the rudder or shag reference numeral 34 of the outboard motor steering housing 10.

In both embodiments the gyroscopic principle, whereby the gyroscope olfers resistance to any torque which would change the direction of the axis of spin, is em;

ployed to resist the torque which is set up by the rotary forces driving the propeller 14.

It is within the purview of the present invention to locate the gyroscope in places other than the propeller drive housing providing such other locations result in the gyroscopic action overcoming propeller drive torque reaction. It is also to be understood that the steerable propeller need not necessarily be of the so-called outboard motor type. It will be apparent that the size and weight of the gyroscope is selected in accordance with the magnitude of the forces which have to beoffset during the normal operation of the vessel.

Having thus fully described the invention, what is claimed as new and desired to be secured by Letters Patent of the United States is:

l. A gyro stabilizing structure for a marine propulsion unit comprising, a gm'oscopic flywheel, a steerable propeller drive housing enclosing said flywheel, a propeller shaft within the said housing, a propeller secured to an extended portion of the free end of the propeller shaft, gear means for driving the flywheel from the propeller shaft, an engine mounted in a fixed position with respect to the hull of the vessel, a vertical drive shaft operatively coupled at one end to the engine and gear means at the other end engaging the propeller shaft, and means to carry the said flywheel so that its axis of spin is normal to the vertical drive shaft, means for carrying the steerable propeller drive housing consisting of, a rotatable supporting member secured to and between the fixed position engine and the said propeller drive housing and enclosing the vertical drive shaft.

2. A gyro stabilizing structure for a marine propulsion unit comprising, a gyroscopic flywheel, a steerable propeller drive housing enclosing said flywheel, a propeller shaft within the said housing, a propeller secured to an extended portion of the free end of the propeller shaft, gear means for driving the flywheel from the propeller shaft comprising a step up gear train connected at its output end to the said flywheel, an engine mounted in a fixed position with respect to the hull of the vessel, a drive shaft operatively coupled at one end to the engine and gear means at the other ,end engaging the propeller shaft, and means to carry the said flywheel so that its axis of spin is normal to the vertical drive shaft, means for carrying the steerable propeller drive housing consisting of, a rotatable supporting member secured to and between the fixed position engine and the said propeller drive housing and enclosing the vertical drive shaft.

3. A gyro stabilizing structure for a marine propulsion unit comprising, a gyroscopic flywheel, a steerable propeller drive housing enclosing said flywheel, a propeller shaft within the said housing, a propeller secured to an extended portion of the free end of the propeller shaft, gear means for driving the flywheel from the propeller shaft comprising a step up gear train connected at its output end to the said flywheel, friction drive means engaging the output end of said step up gears with the flywheel, an engine mounted in a fixed position with respect to thehull of the vessel, a drive shaft operatively coupled at one end to the engine, and gear means at the other end engaging the propeller shaft, and means to carry the said flywheel so that its axis of spin is normal to the vertical drive shaft, means for carrying the steerable propeller drive housing consisting of, a rotatable supporting member secured to and between the fixed position engine and the said propeller drive housing and enclosing the vertical drive shaft.

4. A propulsion unit according to claim 1, in which the propeller drive housing is provided with a downwardly extending rudder portion, and the flywheel is disposed within the said rudder portion having its axis of spin normal to the vertical drive shaft, and means to drive the flywheel from the propeller shaft.

References Cited in the file of this patent UNITED STATES PATENTS 1,326,760 -Macinante Dec. 30, 1919 

